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by armoredkitten 871 days ago
Typically, when I see that it's an indication that the distribution is non-normal. And for anything resembling "count" data (e.g., number of dollars, parts per million, whatever), it's pretty much guaranteed that it will be positively skewed -- because you have a hard lower limit (0) but no upper limit.

That said, I have no expertise with the field of, uhh, toiletology, to know whether they handled this data appropriately or not.

Edit: Sorry, just to add that typically with non-normal data like that, my inclination would be to report the median (which will be less affected by skew than the mean), and perhaps the interquartile distance (difference between the 25th and 75th percentile) rather than SD. But most statistical models are still designed around means and SDs, so you may still be inclined to report means and SDs since that's what you statistically tested for differences.